One of the coolest new features in iOS 11 is also, hopefully, one of the least used. I say it’s hopefully note used that much because it is designed to only be used in emergencies–and obviously the fewer of those, the better.

I’m of course talking about the Emergency SOS feature Apple introduced last autumn. Emergency SOS allows users to quickly call their emergency services number without actually having to have to open the Phone app and dial it.

Using Emergency SOS In iOS 11

Users accomplish this by one of two ways: pressing and holding the side button and volume up button until the Emergency SOS slider appears and then sliding it to call emergency services (on iPhone X, iPhone 8, or iPhone 8 Plus only); or pressing the side button 5 times and then once the Emergency SOS slider appears and then sliding it to call emergency services (on all iPhones rushing iOS 11).

Best of all, after the emergency call ends, Emergency SOS will then send you emergency contacts a text message with your location (unless you cancel this). Hopefully, you’ll never need to use this feature, but if you do it could just save your life.

Enabling Emergency SOS In iOS 11

By default, Emergency SOS should be enabled on all phones running iOS 11. However, if you need to enable it for any reason, the steps are simple:

1. Open the Settings app.
2. Swipe down until you see Emergency SOS and tap it.
3. On the Emergency SOS screen make sure Call with Side Button is enabled.
4. Also, make sure Auto Call is enabled if you want emergency services to be automatically called without needing to slide the Emergency SOS on-screen slider. If this is enabled you’ll see a 3-second countdown on your screen once you’ve activated Emergency SOS. At the end of the timer, emergency services will be called. You can cancel the call at any time during the countdown period.
5. At the bottom of the Emergency SOS settings screen, you can also enable Countdown Sound. This will play an audible warning during the Emergency SOS countdown.

Adding Emergency Contacts To Emergency SOS

If you don’t want to, you don’t need to add emergency contacts. Again, these are the contacts that will get a text message after your call ends with emergency services. However, it’s probably a good idea to add at least one emergency contact so a friend or family member can be notified if you are in trouble. To add an emergency contact to Emergency SOS:

1. Open the Health app on your iPhone.
2. Tap the Medical ID tab.
3. Tap Edit.
4. Under Emergency Contacts, tap the green + button that says “add emergency contact”
5. In the contact slide up sheet, select the contact you want to add and choose their relationship with you.
6. Tap Done to save your changes. Your emergency contacts are now set.